1 files changed, 44 insertions, 0 deletions

diff --git a/scripts/gdb/linux/config.py b/scripts/gdb/linux/config.py
new file mode 100644
index 000000000000..90e1565b1967
--- /dev/null
+++ b/scripts/gdb/linux/config.py
@@ -0,0 +1,44 @@
+# SPDX-License-Identifier: GPL-2.0
+#
+# Copyright 2019 Google LLC.
+
+import gdb
+import zlib
+
+from linux import utils
+
+
+class LxConfigDump(gdb.Command):
+    """Output kernel config to the filename specified as the command
+       argument. Equivalent to 'zcat /proc/config.gz > config.txt' on
+       a running target"""
+
+    def __init__(self):
+        super(LxConfigDump, self).__init__("lx-configdump", gdb.COMMAND_DATA,
+                                           gdb.COMPLETE_FILENAME)
+
+    def invoke(self, arg, from_tty):
+        if len(arg) == 0:
+            filename = "config.txt"
+        else:
+            filename = arg
+
+        try:
+            py_config_ptr = gdb.parse_and_eval("kernel_config_data + 8")
+            py_config_size = gdb.parse_and_eval(
+                    "sizeof(kernel_config_data) - 1 - 8 * 2")
+        except gdb.error as e:
+            raise gdb.GdbError("Can't find config, enable CONFIG_IKCONFIG?")
+
+        inf = gdb.inferiors()[0]
+        zconfig_buf = utils.read_memoryview(inf, py_config_ptr,
+                                            py_config_size).tobytes()
+
+        config_buf = zlib.decompress(zconfig_buf, 16)
+        with open(filename, 'wb') as f:
+            f.write(config_buf)
+
+        gdb.write("Dumped config to " + filename + "\n")
+
+
+LxConfigDump()